The aim of this research was to determine the influence of nitrogen fertilization doses and time of its application on the grain yield, yield components and grain quality of spring wheat cv. Nawra. The field experiment was conducted in 2004-2006 at the Research Station Kepa in Pulawy, Poland. The experiment was conducted in three replications using block methods. Two nitrogen fertilization doses (90 and 180 kg N·ha^-1) and two ways of nitrogen application plus control were used. It was found that the nitrogen fertilization dose affected the grain yield. The lowest grain yield was found for nitrogen application at three times during the vegetation phase, compared with two-time application. This was connected with a smaller number of kernels, lower grain yield per plant and lower productive tillering. The best grain quality parameters were found for a dose of 180 kg N·ha^-1 applied three times during the vegetation period (60 kg before sowing + 60 kg in shooting phase + 60 kg in heading phase).The correlation coefficient indicated a strong relationship between nitrogen fertilization and the grain yield, number of heads, protein content and gluten content in spring wheat grain.

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